Standard Presentation (15 mins) Australian Marine Sciences Association 2022

A two-part seabed geomorphology mapping scheme for multidisciplinary and multiscalar applications (#365)

Rachel A Nanson 1 , Dayton Dove 2 , Riccardo Arosio 3 , Janine Guinan 4 , Lilja Bjarnadóttir 5
  1. Geoscience Australia, Symonston, ACT, Australia
  2. British Geological Survey, Edinburgh, United Kingdom
  3. University College Cork, Cork, Ireland
  4. Geological Survey of Ireland, Cork, Ireland
  5. Geological Survey of Norway, Trondheim, Norway

Seabed geomorphology exerts a first-order control on the distribution of benthic marine ecosystems, and geomorphology maps provide foundational information for a broad range of marine applications. Global realisation of the Blue Economy is driving the proliferation of seabed data acquisition, and the geomorphic characterisation of these data requires standardised multiscalar and interjurisdictional approaches. Geoscience Australia has been collaborating with equivalent organisations in the United Kingdom, Norway and Ireland to develop a two-part marine geomorphology mapping scheme that can meet this global need. Part 1 of this scheme (Morphology: Dove et al., 2020) was published as an illustrated glossary of primarily International Hydrographic Organization terms, and can be applied to bathymetry data. Part 2 (Geomorphology: cf. Nanson et al, 2022) of this approach provides a hierarchical structure and a list of geomorphic terms, derived from published literature, for classifying morphological features identified in Part 1. This second step requires additional seabed data and expert interpretation, incorporating uncertainty in subsurface interpretation. We demonstrate the application of this approach to investigate geomorphic features within Australia’s EEZ, including the reconstruction of the evolution of, and to assess recent seabed changes in, the Perth Canyon.

 

  1. Nanson, R.A., Borissova, I., Huang, Z., Post, A., Nichol, S.L., Spinoccia, M., Siwabessy, J.W., Sikes, E.L. and Picard, K., 2022. Cretaceous to Cenozoic controls on the genesis of the shelf-incising Perth Canyon; insights from a two-part geomorphology mapping approach. Marine Geology, 445, p.106731. https://www.sciencedirect.com/science/article/pii/S0025322722000020
  2. Dove, D., Nanson, R., Bjarnadóttir, L.R., Guinan, J., Gafeira, J., Post, A., Dolan, M.F.J., Stewart, H., Arosio, R. and Scott, G., 2020. A two-part seabed geomorphology classification scheme:(v. 2). Part 1: morphology features glossary. https://zenodo.org/record/4071940#.YiGCSPlBxPY